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Cypress PSOC USB are present on some members of the PSOC family, eg on 24000, which is the only chip containing practically all the PSOC capabilities: digital/analog mixed signal matrix, capsense, USB.

PSOC USB has some limitation. It is true that PSOC implement USB 2.0, but only with a maximum speed of 12 Mb/sec. This is not USB 1.1, as you can be 2.0 compliant, but still unable to go faster than what in USB trade jargon is called “high speed”, that is 12 Megabyte per second.

All you can have is 4 access points plus the control access point, i.e.: as all access point besides the mandatory control point in monodirectional you can have 2 upstrem and 2 downstream, or any combination of 4. The buffers cannot be longer than 1K, and be warned that the PSOC is not a very fast microcontroller either.

A Cypress FAE recommendes sticking to approaches not involving the need for the development of a custom driver. As maximum speed is 12 Mb/sec this approach is viable, as it may involve the development of either a HID based project or USB com emulation, rather than custom driver development, which tends to verge on the really expensive very quickly. A HID (human interface device) does not need a driver as it is part of core Windows driver, and work with ANY versions of Windows, so, no angry calls to support are to be expected.

HID interfaces have recently achieved a speed capability of 12 Mb/sec. previously, this approach was limited to 64K/sec, which is however more than enough for most simple controls, but is not sufficient for those needing bulk data transfers or streaming.

So, PSOCs do not offer all USB 2.0 has to offer, but are a quickpath in getting things done, if your needs don’t involve streaming video in real time or any application requiring a throughput of 480 Mb/sec.

They are simple, and tools are generosly provided by Cypress which simplify the design of HID devices, these tools, with other vendors you either don’t have, or have to pay for. If you want to achieve 480 Mb/sec transfers, other, more specific Cypress components exist which are better suited for the job.

Cypress PSOC, even in USB never really shines in anything but integration: it is a small component which contains an amazing lot of possibilities, e.g.: you can sample a capacitive keyboard, sample and filter a voltage, connect to a wireless radio, drive I2c bus devices, and have USB, all in one chip.

This is a feat no Cypress competitor, at the current state of the art, can claim being able to achieve.

These components have been studied in order to reduce BOM: even the pullup resistors needed by the interface are integrated, because havint to add them externally would involve a more complexity and cost.

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